[net.periphs] need help with 11/750 config for 4.2

yechiel@aecom.UUCP (Yechiel Corn) (09/22/84)

We are planning to run 4.2 on an 11/750. We want to equip it with
an RA-80 with UDA-50 controller, TU-80 tape drive, 1 DZ, and an Able DH/DM.
Is it possible/advisable to put all this on one UBA?  There are enough
backplane slots; this is not the issue. DEC has a
UDA-50 driver for Sys V, and it specifies that it requires its own UBA.
They say its because the UDA-50 uses up too many Address Map Registers
on the Unibus and as a result, the kernel would be severely limited in size.
Does this same restriction apply to 4.2?

Any helpful hints or pointers would be appreciated
Please respond directly by mail to

	{philabs,ihnp4,cucard,rocky2}!aecom!yechiel

Thanks in advance!

				Michael Corn

dave@uwvax.UUCP (Dave Cohrs) (09/30/84)

> They say its because the UDA-50 uses up too many Address Map Registers
> on the Unibus and as a result, the kernel would be severely limited in size.
> Does this same restriction apply to 4.2?

The big restriction with the UDA for UN*X is that it uses up too much of
the bandwidth of the unibus.  If you want to get anything done, you'll
have to run it on a separate unibus (or things will just be slow).

-- 

(Bug?  What bug?  That's a feature!)

Dave Cohrs
...!{allegra,heurikon,ihnp4,seismo,uwm-evax}!dave
dave@wisc-rsch.arpa